In general, follow the capitalization rules of Standard English. The following guidelines discuss the specific capitalization guidelines that are used in Microsoft content:
Never use all uppercase for emphasis. Use sentence structure for emphasis instead. It’s best to avoid formatting for emphasis, but if you must use formatting for emphasis, use italic formatting instead of all uppercase.
Follow the capitalization guidelines or conventions for software or for a specific product or service as necessary, such as case-sensitive keywords or product or service names with internal capitalization.
Do not capitalize the spelled-out form of an acronym unless the spelled-out form is a proper noun. When in doubt, see the Acronyms and other abbreviations, or consult your project style sheet.
Do not use capitalization randomly. Use lowercase unless there is a specific reason for capitalizing.
After consulting your project style sheet and this manual, use the American Heritage Dictionary as the primary reference for proper capitalization of specific words and The Chicago Manual of Style for general guidelines.
As a general rule, be conservative in capitalizing the names of new features and technologies. To determine whether to capitalize a feature or technology name, follow these guidelines:
Capitalize the name for legal reasons, such as efforts to establish a trademark or to respect a trademark registered by another company.
Capitalize the name if it is capitalized in a marketing or branding campaign.
Capitalize the name to distinguish a component or product, such as SQL Server, from a general technology with a similar name, such as an SQL database server.
Capitalize industry-standard terms only if the rest of the industry does so. Search the American Heritage Dictionary, the Internet, and industry-specific dictionaries. Do not rely on unedited websites.
For new names and terms, work toward consistency in capitalization with other company products, services, documents, packaging, and marketing.
Over the years, design guidelines have become less formal, and many groups at Microsoft as well as at other companies are now using sentence-style capitalization for titles and headings. Sentence-style capitalization is also easier for the worldwide audience to read and for machine translation to translate. For these reasons, Microsoft Manual of Style recommends using sentence-style capitalization for titles and all headings, regardless of level.
Microsoft style
Copy music to a CD
Find a file
Not Microsoft style
Copy Music to a CD
Find a File
If your content still uses title capitalization, the following guidelines answer questions about capitalization of various constructions and parts of speech.
Capitalize all nouns, verbs (including is and other forms of be), adverbs (including than and when), adjectives (including this and that), and pronouns (including its).
Capitalize the first and last words, regardless of their parts of speech (“The Text to Look For”).
Capitalize prepositions that are part of a verb phrase (“Backing Up Your Disk”).
Do not capitalize articles (a, an, the) unless the article is the first word in the title.
Do not capitalize coordinate conjunctions (and, but, for, nor, or, yet, so) unless the conjunction is the first word in the title.
Do not capitalize prepositions of four or fewer letters unless the preposition is the first or the last word in the title.
Do not capitalize to in an infinitive phrase (“How to Format Your Hard Disk”) unless the phrase is the first word in the title.
Capitalize the second part of a hyphenated compound if it would be capitalized without the hyphen. Always capitalize the second part of a hyphenated compound if it is the last word of a heading or title.
Microsoft style
Installing Add-ins in Word
Installing an Add-In
Run-Time Error Codes
Not Microsoft style
Installing Add-Ins in Word
Installing an Add-in
Run-time Error Codes
Capitalize user interface and application programming interface terms that you would not ordinarily capitalize unless they are case-sensitive (“The fdisk Command”). Follow the traditional capitalization of keywords and other special terms in programming languages (“The printf Function,” “Using the EVEN and ALIGN Directives”).
For more information, see Lists, Tables.
Always use lowercase after a colon within a sentence, except when:
A colon introduces a direct quotation.
The first word after the colon is a proper noun.
For more information, see Colons (Chapter 9).
Do not capitalize the word following an em dash unless it is a proper noun, even if the text following the em dash is a complete sentence.
Always capitalize the first word of a new sentence. Rewrite sentences that start with a case-sensitive lowercase word.
The printf function is the most frequently used C function.
The most frequently used C function is printf.
Not Microsoft style
printf is the most frequently used C function.
For information about capitalization of user interface elements, see User interface formatting (Chapter 5).